Kensington NeuroBlog 2 : Headaches by Dr Mark Weatherall Consultant Neurologist
Head pains have always been with us. Zeus, the greatest of the Greek Gods, was beset by a tremendous headache after swallowing Metis, the goddess of wisdom, with whom he had conceived a child. His pain was only relieved when Prometheus cleaved his head open with an axe, and the goddess Athena emerged, fully formed, from within his skull: truly, the archetypal ‘splitting headache’.
Most head pains are more humdrum, and less debilitating, but many headaches can be disabling, and a very few portend significant brain problems, so it is a symptom always worth taking seriously.
Headaches are classified according the International Classification of Headache Disorders. The first edition, published in 1988, was the brainchild of the great Danish headache expert Jes Olesen. We are now on version 3-beta. The ICHD divides headaches into primary headache disorders, and secondary headache disorders. Primary headache disorders are conditions with independent pathophysiological mechanisms, to which people are genetically or constitutionally prone; the commonest primary headache is tension-type headache; the commonest debilitating primary headache is migraine. Secondary headache disorders are conditions in which head pain arises from pain-sensitive structures in or around the head, such as the eyes, the sinuses and the neck, or from more generalised problems such as infections or metabolic disturbances. A few of the secondary headache disorders – such as those caused by brain tumours, meningitis, or stroke – are serious, but fortunately these are rare. Even in A&E Departments, only 1 in 50 patients who present with a headache has such a serious underlying cause; most have primary headaches, and most of those are migraines.
So if you have a headache, how do you know what is causing it? The answer is most often in the nature and pattern of the pain, and the associated symptoms. Migraines, for example, tend to be one-sided throbbing headaches, associated with nausea, and/or sensitivity to lights, noises, and movement. Cluster headache (a particularly horrible primary headache disorder variously known as the alarm clock headache (for its tendency to wake people at the same time every night) or the suicide headache (for obvious reasons)) is invariably one-sided, excruciatingly severe, and typically a watering eye, runny nose, and drooping or swelling of the eyelid on the side of the attack.
Headaches due to serious causes often come suddenly out of nowhere (proverbially “like being hit over the head with a baseball bat”), or build up steadily and insidiously without remitting. It is always worth taking new headaches seriously, particularly if they behave like this, or if they are associated with fever, neck stiffness, rash, weakness, or disturbance of vision.
In future blogs I will go into more detail about the some of the more common, and more serious headaches. For now, I will leave you with Ian Fleming, an inveterate headache sufferer, who could not resist, at least once (in the novel Moonraker), saddling James Bond with a headache “sitting over his right eye as if it had been nailed there”. Too many martinis, 007?
By Dr Mark Weatherall, Consultant Neurologist